From 74e3512731bd5c9673176425a76a7cc5efa8ddb6 Mon Sep 17 00:00:00 2001 From: Dmitry Osipenko Date: Wed, 24 Oct 2018 22:37:13 +0300 Subject: [PATCH 1/2] hwmon: (core) Fix double-free in __hwmon_device_register() Fix double-free that happens when thermal zone setup fails, see KASAN log below. ================================================================== BUG: KASAN: double-free or invalid-free in __hwmon_device_register+0x5dc/0xa7c CPU: 0 PID: 132 Comm: kworker/0:2 Tainted: G B 4.19.0-rc8-next-20181016-00042-gb52cd80401e9-dirty #41 Hardware name: NVIDIA Tegra SoC (Flattened Device Tree) Workqueue: events deferred_probe_work_func Backtrace: [] (dump_backtrace) from [] (show_stack+0x20/0x24) [] (show_stack) from [] (dump_stack+0x9c/0xb0) [] (dump_stack) from [] (print_address_description+0x68/0x250) [] (print_address_description) from [] (kasan_report_invalid_free+0x68/0x88) [] (kasan_report_invalid_free) from [] (__kasan_slab_free+0x1f4/0x200) [] (__kasan_slab_free) from [] (kasan_slab_free+0x14/0x18) [] (kasan_slab_free) from [] (kfree+0x90/0x294) [] (kfree) from [] (__hwmon_device_register+0x5dc/0xa7c) [] (__hwmon_device_register) from [] (hwmon_device_register_with_info+0xa0/0xa8) [] (hwmon_device_register_with_info) from [] (devm_hwmon_device_register_with_info+0x74/0xb4) [] (devm_hwmon_device_register_with_info) from [] (lm90_probe+0x414/0x578) [] (lm90_probe) from [] (i2c_device_probe+0x35c/0x384) [] (i2c_device_probe) from [] (really_probe+0x290/0x3e4) [] (really_probe) from [] (driver_probe_device+0x80/0x1c4) [] (driver_probe_device) from [] (__device_attach_driver+0x104/0x11c) [] (__device_attach_driver) from [] (bus_for_each_drv+0xa4/0xc8) [] (bus_for_each_drv) from [] (__device_attach+0xf0/0x15c) [] (__device_attach) from [] (device_initial_probe+0x1c/0x20) [] (device_initial_probe) from [] (bus_probe_device+0xdc/0xec) [] (bus_probe_device) from [] (deferred_probe_work_func+0xa8/0xd4) [] (deferred_probe_work_func) from [] (process_one_work+0x3dc/0x96c) [] (process_one_work) from [] (worker_thread+0x4ec/0x8bc) [] (worker_thread) from [] (kthread+0x230/0x240) [] (kthread) from [] (ret_from_fork+0x14/0x38) Exception stack(0xcf743fb0 to 0xcf743ff8) 3fa0: 00000000 00000000 00000000 00000000 3fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 3fe0: 00000000 00000000 00000000 00000000 00000013 00000000 Allocated by task 132: kasan_kmalloc.part.1+0x58/0xf4 kasan_kmalloc+0x90/0xa4 kmem_cache_alloc_trace+0x90/0x2a0 __hwmon_device_register+0xbc/0xa7c hwmon_device_register_with_info+0xa0/0xa8 devm_hwmon_device_register_with_info+0x74/0xb4 lm90_probe+0x414/0x578 i2c_device_probe+0x35c/0x384 really_probe+0x290/0x3e4 driver_probe_device+0x80/0x1c4 __device_attach_driver+0x104/0x11c bus_for_each_drv+0xa4/0xc8 __device_attach+0xf0/0x15c device_initial_probe+0x1c/0x20 bus_probe_device+0xdc/0xec deferred_probe_work_func+0xa8/0xd4 process_one_work+0x3dc/0x96c worker_thread+0x4ec/0x8bc kthread+0x230/0x240 ret_from_fork+0x14/0x38 (null) Freed by task 132: __kasan_slab_free+0x12c/0x200 kasan_slab_free+0x14/0x18 kfree+0x90/0x294 hwmon_dev_release+0x1c/0x20 device_release+0x4c/0xe8 kobject_put+0xac/0x11c device_unregister+0x2c/0x30 __hwmon_device_register+0xa58/0xa7c hwmon_device_register_with_info+0xa0/0xa8 devm_hwmon_device_register_with_info+0x74/0xb4 lm90_probe+0x414/0x578 i2c_device_probe+0x35c/0x384 really_probe+0x290/0x3e4 driver_probe_device+0x80/0x1c4 __device_attach_driver+0x104/0x11c bus_for_each_drv+0xa4/0xc8 __device_attach+0xf0/0x15c device_initial_probe+0x1c/0x20 bus_probe_device+0xdc/0xec deferred_probe_work_func+0xa8/0xd4 process_one_work+0x3dc/0x96c worker_thread+0x4ec/0x8bc kthread+0x230/0x240 ret_from_fork+0x14/0x38 (null) Cc: # v4.15+ Fixes: 47c332deb8e8 ("hwmon: Deal with errors from the thermal subsystem") Signed-off-by: Dmitry Osipenko Signed-off-by: Guenter Roeck --- drivers/hwmon/hwmon.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/hwmon/hwmon.c b/drivers/hwmon/hwmon.c index 975c95169884..84f61cec6319 100644 --- a/drivers/hwmon/hwmon.c +++ b/drivers/hwmon/hwmon.c @@ -649,8 +649,10 @@ __hwmon_device_register(struct device *dev, const char *name, void *drvdata, if (info[i]->config[j] & HWMON_T_INPUT) { err = hwmon_thermal_add_sensor(dev, hwdev, j); - if (err) - goto free_device; + if (err) { + device_unregister(hdev); + goto ida_remove; + } } } } @@ -658,8 +660,6 @@ __hwmon_device_register(struct device *dev, const char *name, void *drvdata, return hdev; -free_device: - device_unregister(hdev); free_hwmon: kfree(hwdev); ida_remove: From e3e61f01d755188cb6c2dcf5a244b9c0937c258e Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Sun, 28 Oct 2018 18:16:51 +0100 Subject: [PATCH 2/2] hwmon: (ibmpowernv) Remove bogus __init annotations If gcc decides not to inline make_sensor_label(): WARNING: vmlinux.o(.text+0x4df549c): Section mismatch in reference from the function .create_device_attrs() to the function .init.text:.make_sensor_label() The function .create_device_attrs() references the function __init .make_sensor_label(). This is often because .create_device_attrs lacks a __init annotation or the annotation of .make_sensor_label is wrong. As .probe() can be called after freeing of __init memory, all __init annotiations in the driver are bogus, and should be removed. Signed-off-by: Geert Uytterhoeven Signed-off-by: Guenter Roeck --- drivers/hwmon/ibmpowernv.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/hwmon/ibmpowernv.c b/drivers/hwmon/ibmpowernv.c index 0ccca87f5271..293dd1c6c7b3 100644 --- a/drivers/hwmon/ibmpowernv.c +++ b/drivers/hwmon/ibmpowernv.c @@ -181,7 +181,7 @@ static ssize_t show_label(struct device *dev, struct device_attribute *devattr, return sprintf(buf, "%s\n", sdata->label); } -static int __init get_logical_cpu(int hwcpu) +static int get_logical_cpu(int hwcpu) { int cpu; @@ -192,9 +192,8 @@ static int __init get_logical_cpu(int hwcpu) return -ENOENT; } -static void __init make_sensor_label(struct device_node *np, - struct sensor_data *sdata, - const char *label) +static void make_sensor_label(struct device_node *np, + struct sensor_data *sdata, const char *label) { u32 id; size_t n;